Mixed reality-based technology to visualize and facilitate treatment planning of impacted teeth: Proof of concept.

OBJECTIVE: We propose a method utilizing mixed reality (MR) goggles (HoloLens 2, Microsoft) to facilitate impacted canine alignment, as planning the traction direction and force delivery could benefit from 3D data visualization using mixed reality (MR). METHODS: Cone-beam CT scans featuring isometric resolution and low noise-to-signal ratio were semi-automatically segmented in Inobitec software. The exported 3D mesh (OBJ file) was then optimized for the HoloLens 2. Using the Unreal Engine environment, we developed an application for the HoloLens 2, implementing HoloLens SDK and UX Tools. Adjustable pointers were added for planning attachment placement, traction direction, and point of force application. The visualization was presented to participants of a course on impacted teeth treatment, followed by a 10-question survey addressing potential advantages (5-point scale: 1 = totally agree, 5 = totally disagree). RESULTS: Out of 38 respondents, 44.7% were orthodontists, 34.2% dentists, 15.8% dental students, and 5.3% dental technicians. Most respondents (44.7%) were between 35 and 44 years old, and only 1 (2.6%) respondent was 55-64 years old. Median answers for six questions were 'totally agree' (25th percentile 1, 75th percentile 2) and for four questions 'agree' (25th percentile 1, 75th percentile 2). No correlation was found between age, profession, and responses. CONCLUSION: Our method generated substantial interest among clinicians. The initial responses affirm the potential benefits, supporting the continued exploration of MR-based techniques for the treatment of impacted teeth. However, the recommendation for widespread use awaits validation through clinical trials.

Phytocannabinoids and gingival inflammation: Preclinical findings and a placebo-controlled double-blind randomized clinical trial with cannabidiol.

OBJECTIVE: The aim of this study was to: (1) evaluate the anti-inflammatory effects of cannabidiol (CBD) on primary cultures of human gingival fibroblasts (HGFs) and (2) to clinically monitor the effect of CBD in subjects with periodontitis. BACKGROUND: The use of phytocannabinoids is a new approach in the treatment of widely prevalent periodontal disease. MATERIALS AND METHODS: Cannabinoid receptors were analyzed by western blot and interleukin production detected using enzyme immunoassay. Activation of the Nrf2 pathway was studied via monitoring the mRNA level of heme oxygenase-1. Antimicrobial effects were determined by standard microdilution and 16S rRNA screening. In the clinical part, a placebo-control double-blind randomized study was conducted (56 days) in three groups (n = 90) using dental gel without CBD (group A) and with 1% (w/w) CBD (group B) and corresponding toothpaste (group A - no CBD, group B - with CBD) for home use to maintain oral health. Group C used dental gel containing 1% chlorhexidine digluconate (active comparator) and toothpaste without CBD. RESULTS: Human gingival fibroblasts were confirmed to express the cannabinoid receptor CB2. Lipopolysaccharide-induced cells exhibited increased production of pro-inflammatory IL-6 and IL-8, with deceasing levels upon exposure to CBD. CBD also exhibited antimicrobial activities against Porphyromonas gingivalis, with an MIC of 1.5 µg/mL. Activation of the Nrf2 pathway was also demonstrated. In the clinical part, statistically significant improvement was found for the gingival, gingival bleeding, and modified gingival indices between placebo group A and CBD group B after 56 days. CONCLUSIONS: Cannabidiol reduced inflammation and the growth of selected periodontal pathogenic bacteria. The clinical trial demonstrated a statistically significant improvement after CBD application. No adverse effects of CBD were reported by patients or observed upon clinical examination during the study. The results are a promising basis for a more comprehensive investigation of the application of non-psychotropic cannabinoids in dentistry.

The Slavcleft: A Three-Center Study of the Outcome of Treatment of Cleft Lip and Palate Considering Palatal Shape.

The degree of deviation of palatal shape from the norm may reflect facial growth disturbance in cleft lip and palate (CLP). The objective of this study was to compare the palatal morphology in children treated with different surgical protocols. Palatal shape was assessed with geometric morphometrics (GM) including Procrustes superimposition, principal component analysis (PCA), and permutation tests with 10,000 permutations, in 24 children treated with two-stage repair with a late palatoplasty (Prague group; mean age at assessment 8.9 years), 16 children after two-stage repair with early palatoplasty (Bratislava group; mean age 8.2 years), and 53 children treated with a one-stage repair (Warsaw group, mean age 10.3 years). The non-cleft control group comprised 60 children at 8.6 years. The first five principal components (PCs) accounted for a minimum of 5% of the total shape variability (65.9% in total). The Procrustes distance was largest for the Prague vs. Control pair and smallest for the Prague vs. Bratislava pair. Nonetheless, all intergroup differences were statistically significant (p < 0.01). One can conclude that variations in palatal shape roughly correspond to cephalometric and dental arch relationship findings from prior research. Among the children who underwent a one-stage repair of the complete cleft, their palatal morphology most closely resembled that of the non-cleft controls. Conversely, children who received late palatoplasty exhibited the greatest degree of deviation.

Evaluation of the Injection Pain with the Use of Vibraject during Local Anesthesia Injection for Children: A Randomized Clinical Trial.

AIM: To compare the outcomes of the conventional syringe and the outcomes of the vibraject-assisted injection (VAI) in terms of the pain of the needle insertion during various intraoral injections of local anesthesia in children aged 6-9 years. MATERIALS AND METHODS: A total number of 75 children aged 6-9 years were selected from patients visiting the pediatric dental clinic at Damascus University. The children were assigned into three equal groups (25 children each) according to the type of intraoral injection needed for the treatment: Groups [Group I: received upper buccal infiltrations (UBI), Group II: received posterior palatal infiltrations (PPI), and Group III: received inferior alveolar nerve block (IANB)]. This study was conducted considering the split-mouth design. Each child was subjected to both anesthetic injections: the conventional and the vibration-assisted in two separate dental visits 2 weeks apart. At each clinic visit, subjective and objective pain levels were assessed using the visual analog scale (VAS) and Face, Leg, Activity, Cry, Consolability (FLACC) scale. RESULTS: Children who received local anesthesia using the Vibraject method had lower VAS and FLACC scores than those who received local anesthesia using the conventional method. CONCLUSION: Vibraject was more effective in reducing the pain with local anesthetic injection compared to the conventional injection technique in clinical dental procedures for children. CLINICAL SIGNIFICANCE: In a pediatric dental clinic, pain management is considered a pillar that influences actions. Using the VAI may achieve the ease, cooperation, and compliance during the dental care session.

Assessment of the readiness of restorations manufactured by CAD/CAM in terms of marginal fit (Part I).

Background: The master cast is the gold standard for the control and eventual adjustment of restorations produced by conventional procedures. Some digital workflow bypasses the master cast and relies completely on the precision of the CAD/CAM restoration. Aim: To examine the reproducibility of the margins of CAD/CAM restorations generated from a single digital scan. Also, to check the readiness of these restorations for delivery directly after fabrication without adjustment on a master cast and thereby eliminate the need for the master cast. Methods: A total of 18 metal substructures made from cobalt chrome alloy were fabricated utilizing a single STL file. The circumference was divided into eight zones. The vertical marginal discrepancy (VMD) was measured at each zone of each metal substructure, with optical microscopy at ×200 magnification. Results: Measurements of vertical marginal discrepancy were in a range of (-94: 300) with a mean of 62 ± 60 µm. A one-way ANOVA test revealed that the mean VMD is significantly different among the 18 substructures (F17, 1,134 = 63.948, p < 0.001). Conclusion: Although all the received substructures were fabricated from the same scan file, they were not identical and varied widely, and they were going outside the acceptable range in some zones. Within the limitations of this study, the marginal fit can be improved by extraoral adjustments on the master cast. Thus, skipping the master cast deprives the dentist of delivering a restoration of higher quality.

The Short-Term Antibacterial Activity of Three Selected Endodontic Sealers against Enterococcus faecalis Bacterial Culture.

(1) Background: Microorganisms originating from the microflora of the oral cavity are the main cause of the inflammatory diseases of the dental pulp and periapical periodontium, as well as the failure of endodontic treatment. The subsequent root canal treatment is not able to remove all the pathogens, and a small number of viable bacteria remain in the dentine tubules, which must be sealed by endodontic sealers. These sealers should have at least a bacteriostatic effect to prevent the remaining bacteria from reproducing. The aim of this study is to compare the short-term antibacterial activity of three endodontic sealers based on poly-epoxy resin, zinc oxide-eugenol and calcium silicate with a calcium hydroxide-based sealer. Calcium hydroxide is used as temporary intracanal medicament and, thus, should show significant antibacterial activity. (2) Methods: A total of 25 bovine dentine samples infected with Enterococcus faecalis were used in this study. After the sealer placement and a 24 h incubation period, the root canal walls were scraped, and the suspension of dentine fillings was used for a semi-quantitative evaluation of microbial growth. (3) Results: The poly-epoxide resin-based sealer ADSeal™ showed significant antibacterial properties. (4) Conclusions: The highest antibacterial activity was shown in poly-epoxide resin-based sealer group, followed by the zinc oxide-eugenol-based sealer and calcium silicate-based sealer.

Ex Vivo Effect of Novel Lipophosphonoxins on Root Canal Biofilm Produced by Enterococcus faecalis: Pilot Study.

(1) Background: The root canal system has complex anatomical and histological features that make it impossible to completely remove all bacteria by mechanical means only; they must be supplemented with disinfectant irrigation. Current disinfectants are unable to eliminate certain microorganisms that persist in the root canal, resulting in treatment failure. At the Institute of Organic Chemistry and Biochemistry, Prague, novel substances with the bactericidal effect, termed lipophosphonoxins (LPPOs), have been discovered. The aim of this pilot study was to investigate the ex vivo effects of second- and third-generation LPPOs on Enterococcus faecalis and compare them with 5% sodium hypochlorite (NaOCl), 0.12% chlorhexidine digluconate, and 17% ethylenediaminetetraacetic acid (EDTA). (2) Methods: The root canal's dentin was used as a carrier for biofilm formation in the extracted human mature mandibular premolars. The samples were filled with cultivation broth and 0.25% glucose with tested solutions. In control samples, only fresh cultivation broth (negative control) and cultivation broth with bacterial suspension (growth control) were used. Each sample was inoculated with E. faecalis CCM4224 except for the negative control, and cultivation was performed. To determine the number of planktonic cells, the sample content was inoculated on blood agar. To evaluate biofilm formation inhibition, samples were placed in tubes with BHI. (3) Results: LPPOs exhibited a reduction in biofilm growth and bacteria comparable to NaOCl, and they were superior to other tested disinfectants. (4) Conclusions: The study results suggest the effect of lipophosphonoxins on E. faecalis CCM 4224 reduces planktonic bacterial cells and inhibits formation of biofilm in root canal samples.

Effect of assessor's sex on visual color matching in dentistry: A systematic review of the literature.

OBJECTIVES: To evaluate systematically the influence of sex of dental professionals on their capability for visual color matching. MATERIALS AND METHODS: The protocol was registered on PROSPERO (CRD42020205393). PICOS question was develop based on the population, intervention, comparison, outcomes, and study design (PICOS). Eligibility criteria included cross section studies, randomized clinical trials and cohort studies that compared the effect of sex on the visual color matching process. Five electronic databases (Pubmed, Cochrane, EMBASE, Medline, and SCOPUS) and additional literature were screened independently by two researchers in July 2020. Clinical studies evaluating visual color matching skills of dental professionals were included. Studies that did not compare the difference between sexes were excluded. Duplicate articles were removed, titles and abstracts were screened, and studies were selected according to the inclusion criteria. Data were collected and reported in accordance with PRISMA guidelines. Risk of bias was assessed using Joanna Briggs Institute Critical Appraisal Tools. RESULTS: A total of 1192 articles were screened from which 132 full text articles were analyzed and 37 finally included in the systematic review. Most of the studies evaluated the color matching abilities of dental students in vitro with shade tabs or extracted teeth. Out of the 37 articles included, 25 reported no significant difference in shade matching abilities between the sexes. Of the 12 studies that found a significant difference, 11 reported that females had better scores in shade matching exercises. For all studies a low risk of bias was revealed for most of the domains. CONCLUSIONS: While the non-homogeneity of the settings and methods in the included studies make it impossible to construct aggregate statistic, this systematic review suggests that the sex is unlikely to be a critical factor influencing color matching abilities. CLINICAL SIGNIFICANCE: This study suggest that sex of dental professionals does not play a critical factor in matching satisfactory color of future dental restoration with surrounding teeth.

Dental loss after radiotherapy for head and neck cancer.

Introduction In radiotherapy (RT) for head and neck cancer (HNC), dental morbidity is significant and it may result in loss of the dentition following treatment.Aims The aim of this clinical study is to identify the incidence of tooth loss over time and correlate this to the RT dose and various risk factors in patients with HNC treated with radical RT.Design A retrospective observational study.Materials and methods The records of 1,118 patients with HNC treated with radical or adjuvant RT from January 2010 to December 2019 were analysed. After applying strict inclusion criteria, 78 patients with 1,566 individual tooth data were selected. RT dose mapping was performed for each tooth.Results A total of 253 teeth (16.2%) were extracted. The following risk factors were significant: gender (p = 0.0001), xerostomia (p <0.0001), RT dose (p <0.0001) and smoking (p <0.0001). Non-significant factors were age, RT delivery technique and the addition of cisplatin.Conclusion Detailed RT dose mapping was used to identify RT dose as a risk factor for dental loss. Careful pre-RT dental treatment and minimisation of RT dose to teeth and salivary glands is required to prevent or reduce the loss of dentition.

Conservative Treatment of Complicated Crown Fracture and Crown-Root Fracture of Young Permanent Incisor-A Case Report with 24-Month Follow-Up.

The complicated crown-root fracture of young permanent teeth is an uncommon traumatic dental injury that is usually treated in a complex way and is demanding not only for the dentist but even for the treated child. In this case report, we present the conservative treatment of a maxillary central incisor in a 10-year-old boy after a traumatic dental injury. Treatment included partial pulpotomy and adhesive fragment reattachment after reflection of the mucoperiosteal flap. The patient was fully asymptomatic at 24-month follow-up, with an aesthetically acceptable outcome. Vital pulp therapy and adhesive fragment reattachment can be a viable treatment option for complicated crown-root fractures, especially when treating immature permanent teeth.

Clinical and Radiographic Outcomes of Immature Teeth Treated with Different Treatment Protocols of Regenerative Endodontic Procedures: A Retrospective Cohort Study.

Regenerative endodontic procedure (REP) is a progressive treatment modality for immature permanent teeth with necrotic pulp. The ambiguousness about the predictability of REP outcome in relation to complete disinfection of the root canal system and the occurrence of discoloration still exists. The aim of this retrospective study was to analyze two treatment protocols on clinical success rate, radiographic root development and the occurrence of discoloration. Eighteen patients were treated by a single operator by either treatment protocol according to the American Association of Endodontists (AAEP, n = 9) or a modified protocol (MP, n = 9) with the use of 5% sodium hypochlorite and sandblasting. Patients were followed up after 3, 6, 9, 12, 18 and 24 months and clinical success, radiographic root development and the occurrence of discoloration were assessed. The clinical success of MP was significantly higher in two years follow-up (p = 0.015), but the change in radiographic root area was higher for AAEP (p = 0.017) and the occurrence of discoloration was higher in AAEP (p = 0.029). The use of 5% sodium hypochlorite for a longer period of time leads to a higher success rate. The sandblasting of the access cavity reduces the occurrence of discoloration.

Low-level laser therapy effectiveness in reducing initial orthodontic archwire placement pain in premolars extraction cases: a single-blind, placebo-controlled, randomized clinical trial.

BACKGROUND: The objective of this randomized clinical trial was to evaluate Low-Level Laser Therapy (LLLT) effectiveness in spontaneous and chewing pain reduction following initial orthodontic archwire placement. METHODS: 26 patients (mean age 20.07 ± 3.13 years) with maxillary Little's Irregularity Index (LII) of 7 mm or more that indicates first maxillary premolars extraction and no medications intake were eligible for this trial. Patients were randomly assigned with 1:1 ratio using simple randomization technique to receive either LLL or placebo treatment. Blinding was applicable for patients only. In the laser group, patients received a single LLL dose (wavelength 830 nm, energy 2 J/point) in four points (2 buccal, 2 palatal) for each maxillary anterior tooth root. Patients in the placebo group had the same laser application procedure without emitting the laser beam. Patients were asked to score spontaneous and chewing pain intensity by filling out a questionnaire with a 100-mm Visual Analogue Scale (VAS) after 1, 6, 24, 48, and 72 h of treatment application. Independent t-test was used to compare the mean pain scores between the laser and placebo groups for both spontaneous and chewing pain at each studied time point. RESULTS: No dropout occurred so the results of the 26 patients were statistically analyzed. Despite some clinical differences observed between the two groups, no statistical significance was found for each studied time point (p > 0.05) for both spontaneous and chewing pain except after 72 h for chewing pain with a VAS score of (18.84 ± 13.44) mm for the laser group compared to (38.15 ± 27.06) mm for the placebo group. CONCLUSIONS: LLLT, with the suggested parameters, is not effective in pain reduction following initial orthodontic archwire placement. TRIAL REGISTRATION: Name of the registry: Clinicaltrials.gov Trial registration number: NCT02568436. Date of registration: 26 September 2015 'Retrospectively registered'.

Discoloration after Regenerative Endodontic Procedures: A Critical Review.

Discoloration remains an unfavourable complication of otherwise successful regenerative endodontic procedure of immature teeth with necrotic pulp. This review presents a critical view on current knowledge of discoloration sources, its treatment and possible preventive modalities, dealing mainly with the use of antibiotics, ethylendiaminotetraacetic acid, calcium hydroxide, mineral trioxide aggregate, calcium silicate cements, sodium hypochlorite and chlorhexidin during regenerative treatment and their possible interactions. Bleaching as a discoloration treatment modality is discussed as well.

Retreatment of failed revascularization/revitalization of immature permanent tooth - A case report.

The aim of this article is to describe the clinical case of the non-surgical retreatment of a failed revascularization/revitalization treatment (RRT). The retreatment was preceded by two sessions including an interim medication with calcium hydroxide and a modified irrigation protocol containing a highly-concentrated sodium hypochlorite and prolonged usage of ethylenediaminetetraacetic acid (EDTA) to reverse unacceptable side effects of hypochlorite. During a 15- month follow-up, the healing of the periapical lesion, increased thickening of root canal walls and maturation of root was apparent. The repeated RRT represents a possible treatment modality for s failed RRT. Key words:Retreatment, revascularization, revitalization, maturogenesis, immature tooth.

Root Maturation in Teeth Treated by Unsuccessful Revitalization: 2 Case Reports.

This article deals with the unusual course of failed revascularization/revitalization cases. Up to this date the evidence of success and failure rates of revascularization/revitalization treatment is scarce. These case reports present "unsuccessful" revascularization/revitalization treatment of permanent immature teeth with apical periodontitis. Although the teeth were treated by protocol suggested by the American Association of Endodontists and the symptoms disappeared, maturation of teeth continued, and periapical lesion was reduced, the teeth went symptomatic during the follow-up. Subsequently, regular root canal treatment was performed. Despite chronic infection that was probably left inside the root canal after a disinfection protocol, the secondary aims of the treatment were achieved even when the primary ones were not. The possible causes of failures of revascularization/revitalization treatment and their prevention are discussed.